To provide a manufacturing method for a rubber reinforcing wire having an excellent wire drawing property and moreover capable of obtaining a sufficient initial rubber adhesive property.

A brass plating layer is formed on the surface of a high carbon steel wire incorporating carbon of ≥0.70% by a diffusion plating method, and a copper plating layer of 0.02-0.12 μm in thickness is formed on the brass plateing layer. Thereafter, the wire is drawn through a die and drawn at the reduction of area of ≥90% to <98%, and a coated layer obtained by mechanically alloying brass plating and copper plating is formed, whereby the rubber reinforcing wire is manufactured.